How to get started in designing games
There are many ways to build games, and you have almost unlimited options, it's just up to you to pick.

Blender has it's own built-in game engine, but there are other free ones, which many people believe to have superior features, such as Unreal Engine and Unity 3D. You may consider trying one of these options, as they are more widely used.

However, the Blender Game Engine is quickly advancing, and it takes less knowledge of importing/exporting models, and complex graphic knowledge in general, than the other two. Because we are on a Blender forum, I will focus on Blender here.


A good way to get started, is by learning from some simple "project tutorials". Here are some good ones by Born CG.
If you don't know much about coding, and still think making games is for you, now is a good time to learn some code. I recommend Python, as it works well with many programs, including Blender.
Now that you know some code, you can learn how to integrate that code into Blender, or other software. Here's another tutorial.
Now that you know a little bit about it, you can join a project. This can help you to learn other skills, and get in the community. (before you do, you may want to consider how long you are willing to spend on it, so you don't get caught up. A good project that uses Unity and is going somewhere, is here.)


So consider it... and see what you come up with. :)